This invention relates to a mode switching device in a disc playback device used for playing a disc such as a Compact Disc for the Compact Disc Digital Audio System and an optical type video disc.
Construction of a disc playback device will first be described taking a Compact Disc player for example. A Compact Disc player generally automatically transfers a disc inserted in the device to a predetermined playback position in which the disc can be played, feeds an optical pickup head in a radial direction of the disc placed in the playback position and automatically transfers the disc after being played from the playback position to an eject position. For performing these operations, such disc playback device comprises a loading device which performs a loading operation for transferring the disc inserted in the device to the predetermined playback position and an ejecting operation for transferring the disc from the playback position to the eject position, a feed device which performs feeding of the pickup head in the radial direction of the disc and a mode switching device which performs switching of mode between various modes such as loading, playback and eject modes.
As the mode switching device for the disc playback device, it has been proposed to detect movements of some parts of the feed device, loading device and disc driving device by means of suitable detection devices such as microswitches and utilize detection signals provided by such detection devices as mode switching signals. This prior art device, however, necessitates a complicated construction due to limitations in the range of movement of these parts of the respective devices.
It is, therefore, an object of the present invention to provide a mode switching device in a disc playback device of a simplified construction utilizing the existing construction available in the disc playback device.